Laserfiche WebLink
centers with additional support in the form of steel ties every 10 feet. Between the ties and the <br />ditch the sill is filled with ballast material (broken waste rock) to stabilize the track. Most of the <br />openings are created using hand held rock drills (air powered) to drill a pattern of holes that are <br />then loaded with explosives and detonated to break the solid rock into manageable size pieces. <br />The broken rock is then picked up with air powered mucking machines and loaded into mine cars <br />and hauled outside with electric locomotives where it is placed on the Temporary Waste Rock <br />Pile. Basically all of this type of development work is done in host rock that contains little or no <br />mineralization. If a drift or opening is driven on a vein or structure the material is sampled at a <br />close spacing and assayed for elements that may contain value, mainly gold, silver, lead, copper <br />and zinc. If it is determined that the broken material contains value it is diverted to the mill for <br />processing. <br />2.2 Raises <br />Raises are vertical tunnels used to access the blocks of ore in the vein. Most of the raises in this <br />mine were created either as "bald headed" or using an air powered Alimak climber and air <br />powered drills. The technique is essentially the same as for drifts and tunnels, but instead of <br />creating a horizontal opening you are creating a vertical or steeply inclined opening and there is <br />no track used. Once the opening is done it is usually lined with rough cut timbers secured to the <br />walls and ladders are installed so personnel can move up and down from level to level. In the <br />larger opening there is usually an electric powered hoist with a cage (elevator) is installed to <br />move personnel and equipment. Some raises may be installed with via raise boring. In this <br />method a powerful drill machine bores a hole from an upper elevation (or the surface) to an <br />appointed location where there is a large cutter head (4' — 8') attached to the rods, it is then <br />pulled back up to the starting point whilst reaming the opening to the desired diameter. The <br />opening is then fitted with steel ladders and landings. A hoist is installed and used to move <br />personnel and materials up and down. <br />All excavations in the Revenue Mine will be built using methods similar to those described <br />above if not identical. General equipment used in a mine are slushers (air or electric) to move <br />Revenue Mine August 2012 D - <br />